OVERALL SUMMARY AND SPECIFIC AIMS: NETWORK RESOURCE Pharmacogenomics is a multidisciplinary science; it has also become a data-intensive science. Therefore, it requires increasingly clear annotation and representation of phenotypes (disease, adverse event, or clinical and physiological outcomes) to support data integration and cross-database analyses. In fact, the consistent and interpretable characterization of drug-related phenotypes, including treatment response, adverse events, and clinical outcomes, has become a rate-limiting factor in large-scale pharmacogenomic research. We propose a PGRN Network Resource focused on the codification of standardized phenotype definitions and relationships, in coordination with other established government-funded efforts, with a clear and constant focus on pharmacogenomics. Because the standardized representation of phenotypes depends on standards, our first two aims focus on making vocabularies and ontologies (computationally formal vocabularies) about clinical and physiologic concepts accessible and usable to the PGRN community. While necessary, such terminological resources are pedantic absent methods and machinery to integrate them into practical phenotypes. Additionally, we will foster the creation of pharmacogenomically relevant value sets, drawn from standards-based terminologies that satisfy relevant domain-specific requirements, such as anatomy, drug names, or gene names. Finally, a PGRN resource must support outreach to PGRN members and the larger pharmacogenomics community to establish standard phenotypes, stnjctured in a way that these pharmacogenomically relevant phenotypes conform to community and government standards, provide grounding for extension to related conditions, and serve as examples for the broader scientific community. We anticipate that this resource will help to enable consistent and comparable large-scale phenotyping for pharmacogenomics.